Reinforced cast brake shoe



Oct. 20, 1953 c ccu 2,656,022

REINFORCED CAST BRAKE SHOE Original Filed May 31, 1950 IN VEN TOR.

Joseph 0 114050116 AT TOP/V E Y UNITE sra Patented Oct. 20, 1953Original application May 31, 1950, Serial No.

" arer oF 165,303. Divided and this application May 16, 1951-, SerialNo.226,665

2 Claims. (01. 188-258) This invention relates to reinforced cast brakeshoes and more particularly to such brake shoes for a disk brake stator,the .present application "being a division of my 'copending UnitedStates application Serial No. 165,303, filed May 31, 1950.

It is a prime object of the invention to provide a novel, easilyreplaced, reinforced cast brake shoe for use on'such as the stators of adisk brake.

Other objects and advantages of the invention will become apparent fromthe following more detailed description of the invention taken inconnection with the accompanying drawing in which; Fig. 1 is a face viewof a segment of an annular friction element utilizing a plurality ofbrake shoes embodying the invention; Fig. 2 is a cross-sectional viewtaken along the line 2-2 in Fig. 1; Fig. 3 is a "cross-sectional viewtaken along the line 3-3 in Fig. 1; and Fig. l is a perspective view ofa backing plate comprised in the novel brake shoe structure.

Description Referring to the drawing, a friction element utilizing thenovel brake shoe embodying the invention comprises an annular body I andis adapted particularly for use as a non-rotatable braking element of adisk brake by provision of a plurality of aligned, circumferentiallyspacedapart, rectangular openings 4 to accommodate the usualnon-rotatable torque bars (not shown) on which the body I is therebyadapted to be slidably mounted. By sliding movement of the body I on theusual torque bars, braking engagement between the non-rotatable frictionelement and a rotatable friction element or elements (not shown) may beaifected in the well-known manner. Braking torque forces resulting fromsuch braking engagement will be transmitted to the non-rotatable torquebars (not shown) by respective shoulders formed by wear pads 6 welded torespective edges of openings 4. The pads 6 afford a greater bearingsurface for abutment with the torque bars than the thickness of the bodyat openings 6 affords and protects the edges of the openings 4 fromexcessive wear. Termination of braking engagement is eifected byslidable movement of body I on the torque bars (not shown) in adirection away from the rotatable braking element or elements (notshown).

The body A carries a plurality of circumferentially spaced apartremovable brake shoe members 8. Each brake shoe member 8 comprises abacking plate 9 of sheet steel which may be formed by stamping, forexample, and upon one side of which is cast a brake 'shoe I'Ilfor'fiictional interengagement with corresponding shoes on the rotatablebraking element (not shown), the opposite side of said member beingflat'fo r engagement with a flat surface ll: of body 1. Each of thebacking plates 9 is provided with a shoe carrying portion having arectangular shaped slot II midway between the ends of the plate and openat the inner edge of the plate (as mounted on body I), and a pluralityof spaced apart openings I2 at opposite "sides of said slot whichopenings are elongated in the direction of the radius of the body I assaid plate is mounted on said body. The portions or webs I3 providedbetween 'the openings I2 at each side of slots II are pressed out 'ofthe plane of the encircling portion of the plate 9, in a directionawayfrom the side of the plate adapted to engage the body I, a distanceexceeding the thickness of said plate so as to provide at the body side'of each web a recess into and through which molten metal may flow viaand between openings I2 during casting 'of the shoe 'lli onto saidplate, which shoe upon cooling, provides a flat surface of backing plateand shoe for mounting on the smooth plane surface I5 of the annular bodyi. The webs I3 thus beingencircled by metal integral with the metal atthe braking side of the plate acts to securely hold the brake shoe tosaid plate. In the back of each cast shoe I ll within the groove I I isformed, preferably during casting, a rectangular slot I8 to accommodatea torque transmitting lug I9 attached by means of such as welds 2a tothe face I5 at the inner peripheral edge of body I equidistant fromadjacent openings 4. Each of the lugs I9 is preferably rectangular inshape to provide two opposite shoulders extending parallel to a radiusof the body I for free sliding engagement with corresponding shouldersformed by the slot I8 in the shoe it. A slight clearance between torquelugs I9 and shoes ill exists to allow for thermal expansion of suchshoes during heavy prolonged brake application.

Each of the brake shoe members 8 is held in place radially of theannular body I by a retaining pin 2% rigidly attached to said body, bysuch as a weld 25, in radial alignment with one of the lugs I9. Anopening 26 in a projecting portion 28 of each backing plate 9 isprovided to accommodate the pin 26. The length of the shoe carryingportion of the backing plate is less than the distance between adjacentopenings s so that in assembly of the shoe member 8 to the body I, whenthe friction element is in position in a brake, each member may beslipped radially inward of said body between the adjacent respectivetorque bars (not shown) extending through the openings 4 into place onthe lugs l9, and the respective opening 26 in the backing plates 9 maythen be brought into registry with and slipped over the respectiveretaining pin 22. All shoe members 8, once positioned as above, are thenheld so positioned in contact with the surface 55 of the body I by anannular retaining ring 30 removably secured by means such as cap screws3| to said body. The annular retaining ring 38 when in place is disposedadjacent to the outer peripheral edge of the annular body i inengagement with the radially outward projecting ends of each portion 28of the backing plates 9 and covering projecting ends of the retainingpins 24; sockets being provided in said ring at the locations of pins 24to accommodate the ends of same and aid in locating the ring prior toinsertion of cap screws 3|. The projecting ends of each of the portions28 of the backing plates 2 are provided with slots 35 one at either sideof the respective pin 24 and open to the outer edge of the plate throughwhich the cap screws 3i may extend in securing the ring 3i! to the bodyI. The shoe members 8 easily may be removed from the body I, forreplacement, for example, by removal of the cap screws 3| and theretaining ring 30, after which said members may be freed from the pins24 and slipped radially outward from the lugs i9 between openings 4.

It should be pointed out that during employment of the assembledfriction element in a disk brake, when the shoes l0 are in frictionalbraking engagement with other shoes in such brake, torque forcesresultant from such engagement is transmitted substantially directlyfrom the shoes to the body i by way of the lugs I9 in which they are inengagement. The backing plates 9 are subjected to little if any suchtorque forces and act substantially exclusively as mediums through whichthe shoes II] are attached to the body I for carriage thereby.

Summary It will now be seen that I have provided an improved frictionelement particularly adapted for use as a non-rotatable friction brakingelement in a disk brake for railway use, which friction elementcomprises removable friction shoes which are easily replaceable andwhich will not crack or warp with excessive prolonged use.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. In a disk brake or the like, a friction member comprising a flatplate having a slot open to one edge and a plurality of spaced apartwebs pressed from one side of said plate beyond the opposite side adistance exceeding the thickness of said plate and integrally connectedat opposite ends to said plate, and a brake shoe cast on said oppositeside and encircling said webs and the edges of said slot to provide arecess within said slot open to said one edge of said plate, and saidshoe terminating flush with said one side of said plate.

2. In a disk brake or the like, a friction member for an annular brakingelement comprising a flat plate arranged for mounting with one sideagainst said element and having a slot open to an edge inward of saidelement and an opening adjacent an opposite edge of said plate, saidplate having at either side of said slot a plurality of openingselongated in the general direction of the radius of said element andcomprising portions between said openings displaced from said one sideof said plate, and a brake shoe cast on the opposite side of said plate,through said openings and around said displaced portions and over thesides of said slot flush with said one face of said plate.

JOSEPH C. McCUNE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 877,055 Cook Jan. 21, 1908 949,945 Pries Feb. 22, 19101,224,476 McDonough May 1, 1917 2,218,615 McCune Oct. 22, 1940 2,498,501Newell Feb. 21, 1950

